How do i paint plywood board/?

Pramila
by Pramila

I have a three by two feet plywood 5mm board that i want to paint. How do i prime or paint it without it warping? I was told that if I paint a strip corner to corner at the back first and prime the front it will not warp. Is that true?


  13 answers
  • Michelle Leslie Michelle Leslie on Feb 10, 2021

    Hi Pramila, yes that's true. Here's a great article that has a whole bunch of tips on how to stop plywood from warping - http://theplywood.com/flattening-warped

    • Pramila Pramila on Feb 10, 2021

      Thank you, Michelle. great article. I still have a question, though.

      I was told if I paint a broad cross from top left corner to bottom right corner and top right corner to bottom left corner of the back before I paint the whole of the other side, it will prevent the board warping. An artist gave me this tip. My carpenter friend says it won't work. When you said - Yes, that's true- were you agreeing with my artist ? We haven't tried it because the carpenter won't hear of it. I just want to know if this method will work. Have you heard of it or used it?

  • Chloe Crabtree Chloe Crabtree on Feb 10, 2021

    To avoid warping, you've got to seal both surfaces and all four edges. The front and back surfaces should get by with two or three coats. The edges require special attention, because they will just suck up the shellac, so you should give the edges enough coats to really seal them.


    You can read more details here: https://findanyanswer.com/how-do-you-keep-plywood-from-warping#:~:text=To%20avoid%20warping%2C%20you've,coats%20to%20really%20seal%20them.

  • Kathy Gunter Law Kathy Gunter Law on Feb 10, 2021

    I've never had any issues with plywood warping after painting. Make sure it is clean and thoroughly dry. Then prime and paint. Sealing the edges will help to prevent moisture to get in the boards, which is what causing warping.

  • Michelle Leslie Michelle Leslie on Feb 10, 2021

    Hi, we normally seal the edges first (so in your case it will be that thin 5mm edge). Those edges are cut down through the tree rather than across and they will absorb moisture far quicker than the face grain. Sorry, from your question I assumed the corner to corner was referring to the edges, corner to corner. If you don't mind me asking; what are you going to do with the plywood?

  • Vimarhonor Vimarhonor on Feb 10, 2021

    Hello that’s a good question. Also preventatively you might consider using a spray sealer before painting so that significant moisture if using a brush on paint coat formulation will not penetrate. A spray clear sealer, shellac or even aerosol primer might give you that peace of mind.

  • Deb K Deb K on Feb 10, 2021

    Hello Pramila, hope this helps you, I'd gesso both sides, and add supports under it, cradle it like you would a bigger piece. we were taught in painting class to ALWAYS cradle wood, no matter the thickness..it makes for hanging easier as well as helps keep it flat.

  • Sharon Sharon on Feb 10, 2021

    I always use 2 saw horses with some lumber supports to completely support wood when cutting or painting.

  • Morgan McBride Morgan McBride on Feb 10, 2021

    I've never had plywood warp

  • Em Em on Feb 10, 2021

    Paint will not stop a board from warping by painting an X. For protection of the wood you can paint both sides. But warping has nothing to do with adding a coat of paint.

  • Redcatcec Redcatcec on Feb 10, 2021

    Me neither, I have never had plywood warp because of paint. You could put the plywood up on supports to make the painting task easier for you, but that is about it. You may want to ask your friends where they base their theory on facts.

  • Pramila Pramila on Feb 10, 2021

    Hi Everyone. Thank you for your feedback. My carpenter friend knows all the traditional methods. What I wanted to know was whether anyone has heard of this method of painting a cross from top right corner to bottom left corner and top left to bottom right on the back. It was given by an artist, a very good one too. I was told it stops boards from warping. Not sure if it applies to ply. Or to canvases. Unfortunately the artist is no more.

    I want a board for the back of a frame to display a painting. I want it sitting flush on the wall and looking like it's part of the wall. That's why I didn't want any support on the back of the board. The frame will have only top and bottom support on the front of the board. Nothing on the sides so that I can slip my paintings in.

    Will go for the traditional method for now.

    Thank you once again.

  • Annie Annie on Feb 16, 2021

    The plywood shouldnt warp, but your idea for the back first may help, or just paint both sides to completely seal it..

  • Vimarhonor Vimarhonor on Mar 11, 2021

    Yes prime and paint. There are spray paint primers available too.